Предмет: Геометрия, автор: сенеша1995

к окружности с центром точки О и радиусом 9 см проведена касательная CD (С- точка касания) найдите длину отрезка OD если CD=12см

Ответы

Автор ответа: JustDropDead
0

доп. пост. проведем отрезок OD
рассмотрм треугольник OCD, он является прямоугольным (радиус и касательная дают угол в90 градусов) 
далее по теореме пифагора
9^2+12^2=OD^2
ODпримерно равно 15.96872 или корень из 225 

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